A micro-channel heat exchanger has the advantages such as light weight, compact structure, high heat exchange efficiency, all-aluminum material and convenience in recovery, and the like; and at the same time, an internal volume of the micro-channel heat exchanger is small, the filling amount of refrigerant is greatly reduced and thus the micro-channel heat exchanger is widely applied to commercial/domestic air conditioner fields.
In order to obtain corresponding heat exchange amount and energy-efficiency ratio in a limited unit space, a heat exchanger in an air conditioner often needs to be bent to a certain angle to increase a heat exchange area, so as to satisfy the performance requirement during air conditioner design. Simultaneously, air conditioning units in the current market are mostly heat-pump air conditioners which consider refrigeration and heating at the same time. In order to satisfy the demands of air conditioning units for drainage performance during operation in winter, the micro-channel heat exchange is generally designed in such a way that header pipes are horizontally disposed, and flat pipes and fins are vertically disposed. Therefore, the micro-channel heat exchanger needs to be bent along a length direction of the header pipes to form a structure having a designated angle. In a bending process of a traditional micro-channel heat exchanger, fins on an inner side of a bend are squeezed, deformation such as inverted fins and distortion and the like occurs and the circulation of air is thereby obstructed; and fins on an outer side of the bend are stretched, situations such as stretching deformation and even tearing and the like occur, the appearance of the heat exchanger is seriously influenced, and at the same time, since the fins are torn, the heat exchange performance of the heat exchange is decreased.
U.S. patent with publication number U.S. Pat. No. 7,900,689B2 discloses a heat exchanger. In this heat exchanger, a bending part adopts sheet metal parts to replace corrugated fins. Although the problems of inverted fins and distortion are solved, since air cannot smoothly pass through the bending part and the surface area of the sheet metal parts is greatly decreased relative to the surface area of the corrugated fins, a loss is caused to the heat exchange performance of the heat exchanger.